1. Field of the Invention
The invention relates to a device for injecting a fluid into a receptacle filled with fluid, and in particular to a device for an enviromentally neutral and dissipationless exchange of volume between gases and/or liquids under extreme conditions, e.g. in zero gravity in a space laboratory.
2. Description of Related Art
When preserving cells or tissues, a fixing liquid is used. In general, such fixing liquids are toxic so they must not enter the ambient atmosphere. Moreover, a very precise dosing of the fixing liquid is required.
U.S. Pat. No. 4,564,054 describes a transfer device for transferring liquids from a container into a second container closed by a diaphragm, wherein an injection unit with a pair of needles arranged side by side is provided, which are used to pierce the diaphragm simultaneously. One of the needles is connected with a syringe, while, for venting purposes, the other needle communicates with the ambient atmosphere via a filter. When liquid is injected into the second container, air is vented into the environment from this container. Therefore, this system is not suitable for a dissipationless exchange of volume.
It is an object of the present invention to provide a device for injecting a fluid into a receptacle, as well as a receptacle for use with such a device, for a allowing an environmentally neutral and dissipationless exchange of volume in a closed system, while providing for a complete insulation against the environment.